Monport K40 Pro Loud noise and vibration on homing and not moving top left or top right Corner

Issue with Monport K40 Pro (Model MP-3020) Homing and Movement

I recently got a new Monport K40 Pro (Model MP-3020). During the homing process, it creates a loud noise, vibration and the laser does not move to the top left or top right. The homing gets stuck in the middle left, and I am unable to jog the laser towards the top side. I used the default settings taken by LightBurn during installation.

Has anyone encountered a similar issue or have any suggestions on how to fix this? Any help would be greatly appreciated!

Error message shown as below.

Waiting for connection…

Waiting for connection…




Target buffer size found




Homing fail. Could not find limit switch within search distance. Defined as 1.5 * max_travel on search and 5 * pulloff on locate phases.



Grbl 1.1f [‘$’ for help]

[MSG:Check Limits]

[MSG:‘$H’|‘$X’ to unlock]





Grbl 1.1f [‘$’ for help]

[MSG:Check Limits]

[MSG:‘$H’|‘$X’ to unlock]


Hard limit triggered. Machine position is likely lost due to sudden and immediate halt. Re-homing is highly recommended.

[MSG:Reset to continue]


Grbl 1.1f [‘$’ for help]

[MSG:Check Limits]

[MSG:‘$H’|‘$X’ to unlock]

[MSG:Caution: Unlocked]



controller’s firmware version.




Target buffer size found


GRBL settings











































display stored offsets in the machine’s coordinate systems














display status and current position




Can anyone share troubleshooting tips, the correct settings, and the process to edit them for the Monport K40 Pro (Model MP-3020)? Any guidance would be greatly appreciated!

The machine always did that or is a new issue?
Check laser drive system.
Also check for misaligned or twisted motor mount and belts, or debris in the way.

This is either the error or the success… I think you have a hardware issue.


This is always useful and appreciated. Thank you.

The Documentation Team has been Busy!
Alarm 9 is now hot-linked to the Troubleshooting docs.
Click the Blue text above to follow it.

Alarm 9 generally indicates a mechanical problem.
One thing to check that we haven’t seen yet is that the set screws that secure the belt sprockets / or pulleys walk out with use.

Test the set screws with the appropriate Allen Wrench or hex key to ensure they are tight.

Great input. solved.
Wire carrier drag chain was dislocated in transportation and restricting the movement of laser in top direction. Ref pic.

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